No problem. I think the Tactical class is a bit easier for most people than standard. You get one optic in Tactical and most people aren't used to shooting out 100-300 yards with irons (not too mention a good set of national match or globe sights will cost you extra anyhow).
Here's my recommendation for entry level Tactical. Get a 20" gun that is reliable and shoots 1MOA or better. I recommend a 20" gun since it will make Minor Power factor with most off the shelf ammo. You can go standard later if you want to. You can also get it cut to 18" last by a local smith if you want a gun that handles faster (depends on your local three gun courses....are they long or shot in pistol pays?) Mid weight barrel, free floated handguard and a decent brake. Either the F2 brake, PRI QC Brake or Miculek. The F2 and PRI brakes have offset holes to help prevent the recoil to clock up and to the right, but you should be able to see your hits in the scope with any of them.
Optics......for short range/pistol bay only stages, just go red dot. Aimpoint or Eotechs work well, but you really aren't undergunned with a cheapie red dot if it holds zero. For longer ranges, many choose an ACOG or a low powered variable that you can shoot close in with both eyes open. That means the low power should be about 1-3x. My Clark Gator wears a 1.5-5x Simmons Pro Diamond shotgun scope I bought for $50 and I have no need to change it.
Finally.....get a good trigger. The JP trigger or the Jewell if you like a two stage (got used to it on my CMP gun and it's no different than a 1911 two stage break anyhow).
Any gun that runs, shoots 1 MOA, has a decent trigger and fits you can win in 3 gun. You don't really need to pay for cosmetics if you don't want to. AR's are overpriced. By the time you get an off the shelf upper with a decent barrel and add a float tube and brake, you're approaching the cost of the Gator without the .5 MOA gurantee....and without the adjustable gas block and chromed bolt and carrier.
The way I did it: Gator upper for $779
RRA/Stag lower for $220
Jewell trigger for $150
Pro Diamond for $50 (but hard to find them anymore)
The way it shoots in local matches has me spending money on ammo and not on more expensive equipment.